The invention relates to a covering for a gas bag of a vehicle occupant restraint system.
After a gas generator providing compressed gas has been activated, the gas bag is acted upon with pressure so that it presses against the covering. The latter then bursts along a tear line provided in the covering for enabling the gas bag to completely unfold in the vehicle interior and to provide a restraint effect for a vehicle occupant.
The process of the gas bag exiting from the receptacle provided therefor when the covering has opened is decisively influenced by how the covering opens. This in turn depends on the tear line or the tear lines which are provided. The tear lines preferably provide for a uniform opening of the covering without too large a resistance being opposed to the opening process while at the same time a sufficient rigidity is ensured so that the covering is not damaged during normal vehicle operation.
The invention provides a gas bag covering for a vehicle occupant restraint system. The cover is provided with a plurality of tear lines. All of theses tear lines are oriented towards one point. In this manner, the tearing process may be initiated centrally and then continue outwardly so that the individual portions of the covering swing open outwardly and make it possible for the gas bag to unfold unhindered.
According to one embodiment, it is provided for that the tear lines converge at a center point in a star-shaped manner. Thus, the process of opening the covering begins centrally at that point of the covering where the strongest tensions occur when the gas bag presses against the still closed covering from inside.
According to an alternative embodiment, it is provided for that the tear lines terminate at the periphery of an additional tear line which is circular and disposed approximately at the center of the covering. In this configuration, the process of ripping-open is initiated along the circular tear line; it then continues along the rectilinear tear lines oriented towards one point. This configuration makes it possible to provide within the circular tear line a receiving surface for a brand label, for instance.
When a brand label is used, a reinforcement may be attached to the receiving surface constituted by the circular tear line. The reinforcement ensures that the receiving surface together with the brand label is not detached from the covering when the latter is ripped open, but remains reliably connected therewith. The reinforcement may for instance be a sheet metal piece inserted in the covering.
According to an alternative embodiment, it is provided for that the circular tear line is closed in itself and that the receiving surface is connected with a tether. In this configuration, the receiving surface is completely detached from the covering after the circular tear line has initiated the process of ripping-open; the tether is provided in order to prevent the covering from being flung into the vehicle interior by the unfolding gas bag; it ensures that the receiving surface together with the brand label moves along a controlled path.
Advantageous configurations of the invention may be taken from the subclaims.